1. Field of the Invention
This invention relates to a link plate for a metal waste conveyer, particularly to one able to enhance combination strength between the side plates and the flat plates of a metal waste conveyer to prevent the side plates from becoming deformed when they are bumped or pushed by external force.
2. Description of the Prior Art
A metal waste conveyer used for collecting and conveying metal waste is generally assembled at a location where metal waste or parts drop down when a cutting machine is carrying out metal processing, such as a computer milling machine or a computer numerical controlled lathe (CNC lathe). Therefore, the base portion of the left and the right side plate of the conveyer must be strong enough; otherwise the side plates are likely to be bumped and pushed by loading articles and become deformed. Thus, when the conveyer is operated, two adjacent side plates will interfere with and press against each other to produce loss and make noises. Further, the deformed side plates may cause cracks and let metal waste stuck in between two side plates to increase loss and even cause stoppage to the machine.
The link plate of a conventional metal waste conveyer, as shown in FIG. 1, includes a plurality of long rectangular flat plates 10 combined together. Each flat plate 10 has its opposite lengthwise side edges respectively fixed with plural staggered pivotal member 11 formed by bending and rolling up the side edges of the flat plate 10 so that plural flat plates 10 can be pivotally connected in series to make up a ring conveyer belt. Each flat plate 10 has its opposite short ends respectively compressed and formed with a side plate 12 perpendicular to the flat plate 10. The side plates are respectively bent along a lengthwise central line (a) of the flat plate 10 to form a front first superposing surface 121 and a rear second superposing surface 122 so that plural flat plates 10 can be connected together by means of continuous mutual superposition of the first and the second superposing surfaces 121 and 122.
FIG. 2 shows a process of compression molding the link plate of the conventional metal waste conveyer. For elevating the strength of the base portion of the side plate 12, before the side plate 12 is compression molded, the flat plate 10 has the undersides of its opposite short sides respectively compressed upward to form a semi-circular concave recess 13 having its central axial line (b) perpendicular to the lengthwise central line (a) of the flat plate 10 and also intersected with the bending line (c) of the flat plate 10 and the side plate 12. When the semi-circular concave recess 13 is compression molded, the opposite front side of the flat plate 10 will be formed with a lug 14, and after the side plate 12 is compression molded, the lug 14 is located at the intersection portion of the flat plate 10 and the side plate 12. In the course of compression molding the semi-circular concave recess 13, the flat plates 10 and the side plates 12 are once again compressed and squeezed to make their metal molecular structure comparatively close together to elevate the base strength of the side plates 12, and the flat surface of the intersection portion of the flat plate 10 and the side plate 12 is changed into an arc-shaped lug 14 to avoid metal waste staying at the bent corners for reducing loss. In addition, the side plate 12 has its opposite side edges respectively slanting toward the central line (a) of the flat plate 10. Thus, after the first superposing surface 121 of a front side plate 12 is overlapped with the second superposing surface 122 of a rear side plate 12, a gap (d) will be formed on the second superposing face 122 to prevent the lug 14 on the second superposing surface 22 from interfering with the first superposing surface 121. By so designing, a continuous metal waste-receiving groove 15 can be formed for collecting metal waste or parts dropping down when a cutting machine is carrying out metal processing. Then, the metal waste will be conveyed to a gathering site by the conveyer driven by chains 16 that are respectively assembled at the opposite outer sides of the side plates 12.
However, although the lug 14 provided at the intersection portion of the bending line (c) of the flat plate 10 and the side plate 12 can resist stretching of the side plate 12 to avoid destroying its molecule structure when the side plate 12 is compression molded, yet after the side plates 12 are compression molded, the lugs 14 only can a little increase the strength of the base portion of the side plate 12, but cannot elevate the supporting force of the flat plate 10 toward its opposite side plates 12 nor can they enhance the strength of combined stress between the front and the rear flat plate 10.
FIG. 3 shows that the side plate 12 of the link plate of the conventional metal waste conveyer becomes inclined and deformed when it is bumped by external force. If the free ends of the side plates 12 are bumped for long by dropping metal waste or parts, the side plates 12 with insufficient strength at the base portion are likely to be bumped and become slanting inward or outward to let the front and the rear side plate 12 rub each other to produce loss and make noises. In addition, the deformed side plate 12 may cause cracks to let metal waste stuck between two adjacent side plates 12 to hinder the metal filings from conveyed normally.